docs: def addSubsequenceOfFeature(self, parentid):
          """
          This will add reciprocal triples like:
          feature <is subsequence of> parent
          parent has_subsequence feature
          :param graph:
          :param parentid:
  
          :return:
  
          """
          self.graph.addTriple(self.fid, self.globaltt['is subsequence of'], parentid)
          # this should be expected to be done in reasoning not ETL
          self.graph.addTriple(parentid, self.globaltt['has subsequence'], self.fid)
  
          return